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Papers by Carlos H Rodriguez

Research paper thumbnail of Coaction and double-copy properties of configuration-space integrals at genus zero

Journal of High Energy Physics

We investigate configuration-space integrals over punctured Riemann spheres from the viewpoint of... more We investigate configuration-space integrals over punctured Riemann spheres from the viewpoint of the motivic Galois coaction and double-copy structures generalizing the Kawai-Lewellen-Tye (KLT) relations in string theory. For this purpose, explicit bases of twisted cycles and cocycles are worked out whose orthonormality simplifies the coaction. We present methods to efficiently perform and organize the expansions of configuration-space integrals in the inverse string tension α′ or the dimensional-regularization parameter ϵ of Feynman integrals. Generating-function techniques open up a new perspective on the coaction of multiple polylogarithms in any number of variables and analytic continuations in the unintegrated punctures. We present a compact recursion for a generalized KLT kernel and discuss its origin from intersection numbers of Stasheff polytopes and its implications for correlation functions of two-dimensional conformal field theories. We find a non-trivial example of corr...

Research paper thumbnail of Does the Repeal of Mandatory Motorcycle Safety Legislation Affect the Deaths of Motorcyclists? An Autopsy-Based Study Evaluating the Impact of Michigan's Universal Helmet Law Repeal on Immediately Fatal Motorcycle Crashes

Research paper thumbnail of LMB-1 producing Citrobacter freundii from Argentina, a novel player in the field of MBLs

International Journal of Antimicrobial Agents

Research paper thumbnail of Activity Matching with Human Intelligence

Lecture Notes in Business Information Processing, 2016

E↵ective matching of activities is the first step toward successful process model matching and se... more E↵ective matching of activities is the first step toward successful process model matching and search. The problem is nontrivial and has led to a variety of computational similarity metrics and matching approaches, however all still with low performance in terms of precision and recall. In this paper, instead, we study how to leverage on human intelligence to identify matches among activities and show that the problem is not as straightforward as most computational approaches assume. We access human intelligence (i) by crowdsourcing the activity matching problem to generic workers and (ii) by eliciting ground truth matches from experts. The precision and recall we achieve and the qualitative analysis of the results testify huge potential for a human-based activity matching that contemplates disagreement and interpretation.

Research paper thumbnail of An�lisis de red en Salud Mental

Research paper thumbnail of La muerte representada e integración en el duelo

Cultura de los Cuidados Revista de Enfermería y Humanidades, 2001

Research paper thumbnail of Afrontamiento familiar ante la enfermedad mental

Cultura de los Cuidados Revista de Enfermería y Humanidades, 2005

M ental illness has both personal and family implications. Coping strategies and behaviours towar... more M ental illness has both personal and family implications. Coping strategies and behaviours towards disease can change according to resources used. Amongst the resources, the main factor is the family, thus the relevance of the family support network for the management of the person with mental health problems

Research paper thumbnail of Detachable tennis volley practice device

Research paper thumbnail of Assessment of Electron Energy Distributions in Discharges by Optical Emission Spectroscopy

AIP Conference Proceedings, 2007

A procedure for the reconstruction of electron energy distribution functions (EEDF) of low-temper... more A procedure for the reconstruction of electron energy distribution functions (EEDF) of low-temperature neon plasmas from optical emission spectroscopy data is presented. A data descriptive model, including the physics of the plasma discharge and the spectroscopic measurement is developed. Particular refinements of the model regarding the apparatus function of the spectrometer and the optical depth of the plasma for light emission with metastable final states are discussed. The effect of uncertainties in the atomic data entering the model is assessed. Maxwellian and Druyvestein parameterizations for the EEDF are employed. Discrepancies of the reconstructed EEDF with results from independent modelling are not within the error bounds of the data descriptive model.

Research paper thumbnail of Administered activity optimization in 99mTc-MAG3 renography for adults

Journal of Nuclear Medicine Technology, Dec 1, 2003

The objective of this work was to determine the minimum administered activity of 99m Tc-mercaptoa... more The objective of this work was to determine the minimum administered activity of 99m Tc-mercaptoacetyltriglycine (MAG3) needed both to estimate effective renal plasma flow (ERPF) with adequate precision and to obtain good image quality. Methods: Three groups of 10 patients each were injected with 45, 71, or 132 MBq of MAG3. Renograms and perfusion and clearance images were obtained. The age, sex, and weight of the patients; the labeling yield; the mean count and counting rate 2 min after injection; the kidney-to-background and cortex-to-background ratios; the uptake time from the renograms; the percentage of the injected activity 2 min after injection in the left and right kidneys (A2 LK and A2 RK , respectively); and the ERPF for both kidneys were obtained and analyzed. Discriminant analysis of image quality was used to select the variables that most affected image quality. The selected variables were studied among activity groups to optimize the amount of activity administered in these studies. Results: Precision in ERPF assessment did not significantly differ among administered activity levels (P ϭ 0.824). The SDs of the ERPF were Ϯ1.5 for 132 MBq, Ϯ1.7 for 71 MBq, and Ϯ2.0 for 45 MBq. The labeling yield, the ratios of counts in the left and right kidneys to the background and in the left and right cortices to the background, and A2 LK and A2 RK were the only variables that provided a significant discriminant function for image quality. The only variable that significantly differed with the variation in administered activity was the ratio of counts in the right kidney to the background (P ϭ 0.026), most likely because of the labeling yield. Conclusion: A 45-MBq activity is sufficient to guarantee good image quality and adequate precision in ERPF determination from the time-activity curve, provided the labeling yield is kept high.

Research paper thumbnail of Designing Intelligent Instruments

AIP Conference Proceedings, 2007

Remote science operations require automated systems that can both act and react with minimal huma... more Remote science operations require automated systems that can both act and react with minimal human intervention. One such vision is that of an intelligent instrument that collects data in an automated fashion, and based on what it learns, decides which new measurements to take. This innovation implements experimental design and unites it with data analysis in such a way that it completes the cycle of learning. This cycle is the basis of the Scientific Method. The three basic steps of this cycle are hypothesis generation, inquiry, and inference. Hypothesis generation is implemented by artificially supplying the instrument with a parameterized set of possible hypotheses that might be used to describe the physical system. The act of inquiry is handled by an inquiry engine that relies on Bayesian adaptive exploration where the optimal experiment is chosen as the one which maximizes the expected information gain. The inference engine is implemented using the nested sampling algorithm, which provides the inquiry engine with a set of posterior samples from which the expected information gain can be estimated. With these computational structures in place, the instrument will refine its hypotheses, and repeat the learning cycle by taking measurements until the system under study is described within a pre-specified tolerance. We will demonstrate our first attempts toward achieving this goal with an intelligent instrument constructed using the LEGO MINDSTORMS NXT robotics platform.

Research paper thumbnail of Estratégia em ambientes turbulentos

Revista de Administração de Empresas, 2003

Este livro compila artigos apresentados em duas edições de Organization Science de 1996 sobre amb... more Este livro compila artigos apresentados em duas edições de Organization Science de 1996 sobre ambientes hipercompetitivos. Nos vários capítulos, contribuídos por autores de diversas tendências, tanto teóricas como normativas, o livro discute essencialmente o fato de que a competição em tais ambientes exige que as empresas concentrem seus esforços na aquisição de conhecimento, aprendizado e inovação. COMPETING ON THE EDGE: strategy as structured chaos S. L. Brown e K. M. Eisenhardt. Boston : Harvard Business School Press, 1998. 320 p. As contribuições de Eisenhardt para a literatura de estratégia em ambientes de alta velocidade ou rápida mudança foram sistematizadas neste livro de agradável leitura, que pretende apresentar um modelo mais geral, de natureza evolucionária e dinâmica, para empresas que competem em tais cenários. A ênfase é nas iniciativas nas áreas do aprendizado organizacional, que as empresas devem tomar não apenas para permitir que seu estoque de conhecimento possa ser utilizado com sucesso em situações novas, mas também para a aquisição de flexibilidade estrutural para as necessárias mudanças.

Research paper thumbnail of Afilia��o religiosa e empreendedorismo �tnico: o caso dos brasileiros nos Estados Unidos

Research paper thumbnail of Analysis and improvement of business process models using spreadsheets

Information Systems, 2015

Software in general is thoroughly analyzed before it is released to its users. Business processes... more Software in general is thoroughly analyzed before it is released to its users. Business processes often are notat least not as thoroughly as it could bebefore they are released to their users, e.g., employees or software agents. This paper ascribes this practice to the lack of suitable instruments for business process analysts, who design the processes, and aims to provide them with the necessary instruments to allow them to also analyze their processes. We use the spreadsheet paradigm to represent business process analysis tasks, such as writing metrics and assertions, running performance analysis and verification tasks, and reporting on the outcomes, and implement a spreadsheet-based tool for business process analysis. The results of two independent user studies demonstrate the viability of the approach.

Research paper thumbnail of Los efectos externos de la inversión extranjera directa: el caso del "Celtic Tiger", Irlanda

Research paper thumbnail of Um Simulador 3D para Destiladora de Petróleo

Resumo. A destilação é um processo de extrema importância para a indústria de petróleo. Tal proce... more Resumo. A destilação é um processo de extrema importância para a indústria de petróleo. Tal processo é realizado por equipamentos complexos e caros. Para poupar tempo e recursos há a necessidade de ferramentas que simulem sua utilização e auxiliem no seu aprendizado. Este trabalho apresenta um simulador 3D de uma unidade de destilação de petróleo que permite visualizar todas as etapas do seu processo de destilação.

Research paper thumbnail of Asociación de otras drogas de abuso en la intoxicación por cocaína

Research paper thumbnail of Prospectiva UN Agendas de Conocimiento - Construcción de ciudadanía e inclusión social

Research paper thumbnail of Church Membership, Social Capital, and Entrepreneurship in Brazilian Communities in the U.S

International Research in the Business Disciplines, 2003

... metropolitan area, mostly in the cities of Cambridge, Somerville, Marlborough, Framingham, Al... more ... metropolitan area, mostly in the cities of Cambridge, Somerville, Marlborough, Framingham, Allston, Brighton ... cities of Somerville and Allston, which show high concentrations of Brazilianimmigrants and ethnic ... suggested to be the home of the largest number of Brazilian firms in ...

Research paper thumbnail of Peter and the Wolf

A Case a Week: Sleep Disorders from the Cleveland Clinic, 2010

Research paper thumbnail of Coaction and double-copy properties of configuration-space integrals at genus zero

Journal of High Energy Physics

We investigate configuration-space integrals over punctured Riemann spheres from the viewpoint of... more We investigate configuration-space integrals over punctured Riemann spheres from the viewpoint of the motivic Galois coaction and double-copy structures generalizing the Kawai-Lewellen-Tye (KLT) relations in string theory. For this purpose, explicit bases of twisted cycles and cocycles are worked out whose orthonormality simplifies the coaction. We present methods to efficiently perform and organize the expansions of configuration-space integrals in the inverse string tension α′ or the dimensional-regularization parameter ϵ of Feynman integrals. Generating-function techniques open up a new perspective on the coaction of multiple polylogarithms in any number of variables and analytic continuations in the unintegrated punctures. We present a compact recursion for a generalized KLT kernel and discuss its origin from intersection numbers of Stasheff polytopes and its implications for correlation functions of two-dimensional conformal field theories. We find a non-trivial example of corr...

Research paper thumbnail of Does the Repeal of Mandatory Motorcycle Safety Legislation Affect the Deaths of Motorcyclists? An Autopsy-Based Study Evaluating the Impact of Michigan's Universal Helmet Law Repeal on Immediately Fatal Motorcycle Crashes

Research paper thumbnail of LMB-1 producing Citrobacter freundii from Argentina, a novel player in the field of MBLs

International Journal of Antimicrobial Agents

Research paper thumbnail of Activity Matching with Human Intelligence

Lecture Notes in Business Information Processing, 2016

E↵ective matching of activities is the first step toward successful process model matching and se... more E↵ective matching of activities is the first step toward successful process model matching and search. The problem is nontrivial and has led to a variety of computational similarity metrics and matching approaches, however all still with low performance in terms of precision and recall. In this paper, instead, we study how to leverage on human intelligence to identify matches among activities and show that the problem is not as straightforward as most computational approaches assume. We access human intelligence (i) by crowdsourcing the activity matching problem to generic workers and (ii) by eliciting ground truth matches from experts. The precision and recall we achieve and the qualitative analysis of the results testify huge potential for a human-based activity matching that contemplates disagreement and interpretation.

Research paper thumbnail of An�lisis de red en Salud Mental

Research paper thumbnail of La muerte representada e integración en el duelo

Cultura de los Cuidados Revista de Enfermería y Humanidades, 2001

Research paper thumbnail of Afrontamiento familiar ante la enfermedad mental

Cultura de los Cuidados Revista de Enfermería y Humanidades, 2005

M ental illness has both personal and family implications. Coping strategies and behaviours towar... more M ental illness has both personal and family implications. Coping strategies and behaviours towards disease can change according to resources used. Amongst the resources, the main factor is the family, thus the relevance of the family support network for the management of the person with mental health problems

Research paper thumbnail of Detachable tennis volley practice device

Research paper thumbnail of Assessment of Electron Energy Distributions in Discharges by Optical Emission Spectroscopy

AIP Conference Proceedings, 2007

A procedure for the reconstruction of electron energy distribution functions (EEDF) of low-temper... more A procedure for the reconstruction of electron energy distribution functions (EEDF) of low-temperature neon plasmas from optical emission spectroscopy data is presented. A data descriptive model, including the physics of the plasma discharge and the spectroscopic measurement is developed. Particular refinements of the model regarding the apparatus function of the spectrometer and the optical depth of the plasma for light emission with metastable final states are discussed. The effect of uncertainties in the atomic data entering the model is assessed. Maxwellian and Druyvestein parameterizations for the EEDF are employed. Discrepancies of the reconstructed EEDF with results from independent modelling are not within the error bounds of the data descriptive model.

Research paper thumbnail of Administered activity optimization in 99mTc-MAG3 renography for adults

Journal of Nuclear Medicine Technology, Dec 1, 2003

The objective of this work was to determine the minimum administered activity of 99m Tc-mercaptoa... more The objective of this work was to determine the minimum administered activity of 99m Tc-mercaptoacetyltriglycine (MAG3) needed both to estimate effective renal plasma flow (ERPF) with adequate precision and to obtain good image quality. Methods: Three groups of 10 patients each were injected with 45, 71, or 132 MBq of MAG3. Renograms and perfusion and clearance images were obtained. The age, sex, and weight of the patients; the labeling yield; the mean count and counting rate 2 min after injection; the kidney-to-background and cortex-to-background ratios; the uptake time from the renograms; the percentage of the injected activity 2 min after injection in the left and right kidneys (A2 LK and A2 RK , respectively); and the ERPF for both kidneys were obtained and analyzed. Discriminant analysis of image quality was used to select the variables that most affected image quality. The selected variables were studied among activity groups to optimize the amount of activity administered in these studies. Results: Precision in ERPF assessment did not significantly differ among administered activity levels (P ϭ 0.824). The SDs of the ERPF were Ϯ1.5 for 132 MBq, Ϯ1.7 for 71 MBq, and Ϯ2.0 for 45 MBq. The labeling yield, the ratios of counts in the left and right kidneys to the background and in the left and right cortices to the background, and A2 LK and A2 RK were the only variables that provided a significant discriminant function for image quality. The only variable that significantly differed with the variation in administered activity was the ratio of counts in the right kidney to the background (P ϭ 0.026), most likely because of the labeling yield. Conclusion: A 45-MBq activity is sufficient to guarantee good image quality and adequate precision in ERPF determination from the time-activity curve, provided the labeling yield is kept high.

Research paper thumbnail of Designing Intelligent Instruments

AIP Conference Proceedings, 2007

Remote science operations require automated systems that can both act and react with minimal huma... more Remote science operations require automated systems that can both act and react with minimal human intervention. One such vision is that of an intelligent instrument that collects data in an automated fashion, and based on what it learns, decides which new measurements to take. This innovation implements experimental design and unites it with data analysis in such a way that it completes the cycle of learning. This cycle is the basis of the Scientific Method. The three basic steps of this cycle are hypothesis generation, inquiry, and inference. Hypothesis generation is implemented by artificially supplying the instrument with a parameterized set of possible hypotheses that might be used to describe the physical system. The act of inquiry is handled by an inquiry engine that relies on Bayesian adaptive exploration where the optimal experiment is chosen as the one which maximizes the expected information gain. The inference engine is implemented using the nested sampling algorithm, which provides the inquiry engine with a set of posterior samples from which the expected information gain can be estimated. With these computational structures in place, the instrument will refine its hypotheses, and repeat the learning cycle by taking measurements until the system under study is described within a pre-specified tolerance. We will demonstrate our first attempts toward achieving this goal with an intelligent instrument constructed using the LEGO MINDSTORMS NXT robotics platform.

Research paper thumbnail of Estratégia em ambientes turbulentos

Revista de Administração de Empresas, 2003

Este livro compila artigos apresentados em duas edições de Organization Science de 1996 sobre amb... more Este livro compila artigos apresentados em duas edições de Organization Science de 1996 sobre ambientes hipercompetitivos. Nos vários capítulos, contribuídos por autores de diversas tendências, tanto teóricas como normativas, o livro discute essencialmente o fato de que a competição em tais ambientes exige que as empresas concentrem seus esforços na aquisição de conhecimento, aprendizado e inovação. COMPETING ON THE EDGE: strategy as structured chaos S. L. Brown e K. M. Eisenhardt. Boston : Harvard Business School Press, 1998. 320 p. As contribuições de Eisenhardt para a literatura de estratégia em ambientes de alta velocidade ou rápida mudança foram sistematizadas neste livro de agradável leitura, que pretende apresentar um modelo mais geral, de natureza evolucionária e dinâmica, para empresas que competem em tais cenários. A ênfase é nas iniciativas nas áreas do aprendizado organizacional, que as empresas devem tomar não apenas para permitir que seu estoque de conhecimento possa ser utilizado com sucesso em situações novas, mas também para a aquisição de flexibilidade estrutural para as necessárias mudanças.

Research paper thumbnail of Afilia��o religiosa e empreendedorismo �tnico: o caso dos brasileiros nos Estados Unidos

Research paper thumbnail of Analysis and improvement of business process models using spreadsheets

Information Systems, 2015

Software in general is thoroughly analyzed before it is released to its users. Business processes... more Software in general is thoroughly analyzed before it is released to its users. Business processes often are notat least not as thoroughly as it could bebefore they are released to their users, e.g., employees or software agents. This paper ascribes this practice to the lack of suitable instruments for business process analysts, who design the processes, and aims to provide them with the necessary instruments to allow them to also analyze their processes. We use the spreadsheet paradigm to represent business process analysis tasks, such as writing metrics and assertions, running performance analysis and verification tasks, and reporting on the outcomes, and implement a spreadsheet-based tool for business process analysis. The results of two independent user studies demonstrate the viability of the approach.

Research paper thumbnail of Los efectos externos de la inversión extranjera directa: el caso del "Celtic Tiger", Irlanda

Research paper thumbnail of Um Simulador 3D para Destiladora de Petróleo

Resumo. A destilação é um processo de extrema importância para a indústria de petróleo. Tal proce... more Resumo. A destilação é um processo de extrema importância para a indústria de petróleo. Tal processo é realizado por equipamentos complexos e caros. Para poupar tempo e recursos há a necessidade de ferramentas que simulem sua utilização e auxiliem no seu aprendizado. Este trabalho apresenta um simulador 3D de uma unidade de destilação de petróleo que permite visualizar todas as etapas do seu processo de destilação.

Research paper thumbnail of Asociación de otras drogas de abuso en la intoxicación por cocaína

Research paper thumbnail of Prospectiva UN Agendas de Conocimiento - Construcción de ciudadanía e inclusión social

Research paper thumbnail of Church Membership, Social Capital, and Entrepreneurship in Brazilian Communities in the U.S

International Research in the Business Disciplines, 2003

... metropolitan area, mostly in the cities of Cambridge, Somerville, Marlborough, Framingham, Al... more ... metropolitan area, mostly in the cities of Cambridge, Somerville, Marlborough, Framingham, Allston, Brighton ... cities of Somerville and Allston, which show high concentrations of Brazilianimmigrants and ethnic ... suggested to be the home of the largest number of Brazilian firms in ...

Research paper thumbnail of Peter and the Wolf

A Case a Week: Sleep Disorders from the Cleveland Clinic, 2010